SketchSet: creating Euler diagrams using pen or mouse

Euler diagrams form the basis of various visual languages but tool support for creating them is generally limited to generic diagram editing software using mouse and keyboard interaction. A more natural and convenient mode of entry is via a sketching interface which facilitates greater cognitive focus on the task of diagram creation. Previous work has developed sketching interfaces for Euler diagrams drawn with ellipses. This paper presents SketchSet, the first sketch tool for Euler diagrams whose curves can be circles, ellipses, or arbitrary shapes. SketchSet allows the creation of formal diagrams via point and click interaction. The user drawn diagram, in sketched or formal format, is automatically converted to a diagram in the other format, thus maintaining both views. We provide a mechanism that allows semantic differences between the sketch and the formal diagram to be rectified automatically. Finally, we present a user study that evaluates the effectiveness of the tool.